Acupoint catgut embedding for improving HOMA-IR in patients with abdominal obesity and insulin resistance: a protocol for systematic review and network meta-analysis.

Objective: Acupoint catgut embedding (ACE) shows promise for improving insulin resistance in abdominal obesity, but its comparative efficacy against other interventions remains unclear due to a lack of head-to-head trials. This study aims to systematically evaluate the efficacy and safety of ACE for reducing HOMA-IR in this population and to compare different interventions via network meta-analysis. Methods: We will conduct a systematic search of 13 electronic databases, covering the period from the inception of each database to March 2026. This study will include all randomized controlled trials evaluating acupoint catgut embedding for the treatment of abdominal obesity with concomitant insulin resistance. Two review authors will independently perform literature screening, data extraction, and assess the risk of bias of included studies using the revised Cochrane risk-of-bias tool (RoB 2). The primary outcome measure will be the homeostasis model assessment of insulin resistance (HOMA-IR) index. Secondary outcome measures will include fasting plasma glucose, fasting insulin, waist circumference, body mass index, lipid profile, inflammatory markers, and adverse events. Data synthesis will be performed using Stata 17.0 and R software. Conventional pairwise meta-analyses will be conducted using random-effects models. For network meta-analysis, we will adopt a frequentist framework using multivariate random-effects meta-analysis. The design-by-treatment interaction model will be used to assess global inconsistency, and node-splitting analysis will be performed to evaluate local inconsistency for any closed loops in the evidence network. The surface under the cumulative ranking curve (SUCRA) will be used to estimate the probability of each intervention being ranked as the most effective. The strength of evidence will be assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework. Conclusion: This study will compare the efficacy of acupoint catgut embedding against lifestyle interventions, pharmacotherapy, and other acupuncture modalities in improving insulin resistance among patients with abdominal obesity. The findings aim to inform clinical decisions and optimize therapeutic strategies. Additionally, subgroup analyses based on embedding depth, treatment frequency, ethnicity, and insulin resistance severity will help identify the most effective regimens for specific patient subgroups, guiding personalized treatment. Systematic review registration: https://www.crd.york.ac.uk/prospero/, CRD420261331031.